In a virtualized computer environment, virtual machines are configured to run on one or more host computers. Each virtual machine uses CPU and memory resources of one of the host computers and runs its own operating system and application programs to give the appearance that it is operating as a stand-alone computer system. The amount of CPU and memory resources for each of the virtual machines on a host computer can be designated manually by an administrator of the virtualized computer environment or automatically according to resource policies set by the administrator. In some virtualized computer environments, load balancing is enforced across multiple host computers by software that monitors resource usage on different host computers and migrates one or more virtual machines from one host computer to another, e.g., from a busy host computer to one that has excess capacity.
Currently, the ability for an administrator of a virtualized computer environment to visualize the effectiveness of load balancing and/or resource policies is limited. Many virtualized computer environments provide the administrator with a resource graph that shows overall CPU utilization for each of the host computers but displays no information about resources being provided to the individual virtual machines. Some virtualized computer environments provide several types of resource utilization information over a set of displays, each of which is tailored to present a different type of information. Such methods of conveying resource utilization information are not particularly useful because it is difficult to correlate data in the multiple displays, and it is seldom obvious which display contains relevant information.